We already knew the rent was too damn high in San Francisco, even before we published a report this February showing not only that the median for a one bedroom apartment in the city had jumped to $3,460, but that even formerly cheaper neighborhoods were now among the pricey. (To check out a map of the city's crazy rents by 'nabe, go here.)

Apparently though, they weren't high enough. According to Zillow, the new median rent in San Francisco is $4,225 a month. Zillow's data make upe the "Zillow Rental Index" (ZRI). This index shows rents up 16percent year-over-year this April, and take into account all types of rentals in San Francisco proper, from single-family homes to condos to in-laws.

Seattle doesn't come off cheap, but may look that way if you are trying to rent in San Francisco. The index puts median rent here at $2,2258, up nearly 11 percent year over year. The index pegged median rent in Portland at $1,683, up nearly 12 percent

Metro metrics

The whole Bay Area, in fact, shows a rental market on fire. Increased rents in Oakland (up 21.6%); Berkeley (up 30.9%); Emeryville (up 29.5); San Jose (up 14% ) and even Daly City (up 201.1%) make the San Francisco Metropolitan region the fastest growing rental market in the USA.

Each month seems to bring fresh horror for renters in San Francisco – reportedly, even well-paid tech employees are looking elsewhere at this point. We have to ask, readers, at what point is "too high" actually too high?

Anna Marie Erwert writes from both the renter and new buyer perspective, having (finally) achieved both statuses. She focuses on national real estate trends, specializing in the San Francisco Bay Area and Pacific Northwest. Follow Anna on Twitter: @AnnaMarieErwert